Add Richard Sherman to the list of players who do not like the NFL's new helmet rule.

In a series of tweets Sunday, the 49ers cornerback expressed his frustration. He called the new policy, which was put into place this offseason in an effort to protect players, "idiotic" and said the NFL "will be flag football soon."

Sherman started his rant by responding to a tweet posted by Brett Tessler, an NFL agent representing 49ers' Raheem Mostert. Sherman's teammate was penalized for a tackle made in Saturday’s preseason game and Tessler questioned an unnecessary roughness call against his client for leading with the head.

“To all those ppl including those who made the rule. I want a video of YOU running full speed and being lead by anything but your head while also attempting to bring down a moving target,” Sherman wrote Sunday. “You will soon realize it’s impossible.”

To all those ppl including those who made the rule. I want a video of YOU running full speed and being lead by anything but your head while also attempting to bring down a moving target. You will soon realize it’s impossible. https://t.co/QFyENU6LKf

Sherman added in a separate tweet there's no way to adjust how players tackle and said the policy should be "dismissed immediately."

There is no “make adjustment” to the way you tackle. Even in a perfect form tackle the body is led by the head. The rule is idiotic And should be dismissed immediately. When you watch rugby players tackle they are still lead by their head. Will be flag football soon.

“There is no ‘make adjustment’ to the way you tackle,” Sherman continued on Twitter. “Even in a perfect form tackle the body is led by the head. The rule is idiotic And should be dismissed immediately. When you watch rugby players tackle they are still lead by their head. Will be flag football soon."

NFL owners in May approved the new rule, which states, "It is a foul if a player lowers his head to initiate and make contact with his helmet against an opponent."

The new policy applies to all players on the field at all times, and contact does not have to be to an opponent’s head or neck area. Lowering the head and initiating contact to an opponent’s torso, hips or lower body can also result in a penalty (loss of 15 yards). A player also can be ejected from the game.